Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Photoreceptors and Plant Responses to Light02:00

Photoreceptors and Plant Responses to Light

28.3K
Light plays a significant role in regulating the growth and development of plants. In addition to providing energy for photosynthesis, light provides other important cues to regulate a range of developmental and physiological responses in plants.
28.3K
Photosystem I01:27

Photosystem I

69.5K
Although structurally similar to photosystem II (PSII), photosystem I (PSI) is has a different electron supplier and electron acceptor.
Both these photosystems work in concert. An excited electron from PSII is relayed to PSI via an electron transport chain in the thylakoid membrane of the chloroplast, which is comprised of the carrier molecule plastoquinone, the dual-protein cytochrome complex, and plastocyanin. As electrons move between PSII and PSI, they lose energy and must be re-energized...
69.5K
Photosystem II01:22

Photosystem II

78.4K
The multi-protein complex photosystem II (PS II) harvests photons and transfers their energy through its bound pigments to its reaction center, and ultimately to photosystem I (PSI) through the electron transport chain. The pigments responsible for caputirng the light energy in photosystems include chlorophyll a, chlorophyll b, and carotenoids.
The pigment molecules are arranged across  two photosystem domains — the antenna complex and the reaction center. The main aim of the pigment...
78.4K
Photosystems01:32

Photosystems

6.9K
Photosystems are multiprotein complexes that form the functional units of photosynthesis in plants, algae, and cyanobacteria. They are found embedded in the membrane of tiny sac-like structures called thylakoids placed inside the chloroplast.
Functioning of Photosystems
Photosystems contain many pigment molecules, such as chlorophylls and carotenoids, arranged in a particular organization across two domains — the antenna complex and the reaction center. The main aim of the pigment...
6.9K
The Antenna Complex01:15

The Antenna Complex

7.7K
Plants and other photosynthetic organisms comprise pigments capable of absorption of direct sunlight. These pigments are present in the reaction center - the main site of photochemical reactions as well as in the antenna complex. Under average light conditions, the rate at which reaction center pigments absorb light is far below the electron transport chain's capacity. As a result, the reaction center alone cannot provide enough energy to drive photosynthesis. The photosynthetic efficiency can...
7.7K
The Photochemical Reaction Center01:29

The Photochemical Reaction Center

5.3K
Reaction centers are pigment-protein complexes that initiate energy conversion from photons to chemical entities. Therefore, photochemical reaction center is a more appropriate term that describes these complexes. The Nobel laureates Robert Emerson and William Arnold provided the first experimental evidence of photochemical reaction centers by demonstrating the participation of nearly 2,500 chlorophyll molecules for the release of just one molecule of oxygen. Despite thousands of photosynthetic...
5.3K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Molecular Mechanism of the Catalytic Radical Termination in Fatty Acid Photodecarboxylase.

Journal of the American Chemical Society·2026
Same author

Identifying Two New Ros/MucR Proteins: An Atypical Structure with a Divergent Function.

Biomolecules·2026
Same author

Modeling Xanthophyll Excited States via Cost-Effective Quantum Chemistry methods and Property-Based Diabatization.

Journal of chemical theory and computation·2026
Same author

The Newton-X platform for mixed quantum-classical dynamics.

Physical chemistry chemical physics : PCCP·2026
Same author

Making excited state MD faster: Extrapolation of transition densities for TD-DFT calculations.

The Journal of chemical physics·2026
Same author

Vibronic Reorganization Suppresses Salinixanthin-to-Retinal Energy Transfer in the Freshwater Kin4B8 Xanthorhodopsin.

The journal of physical chemistry letters·2026

Related Experiment Video

Updated: Jan 17, 2026

Purification of Active Photosystem I-Light Harvesting Complex I from Plant Tissues
07:10

Purification of Active Photosystem I-Light Harvesting Complex I from Plant Tissues

Published on: February 3, 2023

1.6K

Structural determinants for red-shifted absorption in higher-plants Photosystem I.

Stefano Capaldi1, Zeno Guardini1, Daniele Montepietra1

  • 1Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134, Verona, Italy.

The New Phytologist
|September 16, 2025
PubMed
Summary

Higher plants capture more light in shaded conditions using specialized chlorophylls (Chls) in Photosystem I (PSI). This study reveals precise chromophore interactions are key for far-red light absorption, crucial for optimizing light-harvesting complexes.

Keywords:
LhcaPhotosystem Ifar‐redlight‐harvestinglow‐energy absorptionphotosynthesisred forms

More Related Videos

Evaluation of Photosynthetic Behaviors by Simultaneous Measurements of Leaf Reflectance and Chlorophyll Fluorescence Analyses
10:20

Evaluation of Photosynthetic Behaviors by Simultaneous Measurements of Leaf Reflectance and Chlorophyll Fluorescence Analyses

Published on: August 9, 2019

13.2K
Separation of Spinach Thylakoid Protein Complexes by Native Green Gel Electrophoresis and Band Characterization using Time-Correlated Single Photon Counting
08:40

Separation of Spinach Thylakoid Protein Complexes by Native Green Gel Electrophoresis and Band Characterization using Time-Correlated Single Photon Counting

Published on: February 14, 2019

8.7K

Related Experiment Videos

Last Updated: Jan 17, 2026

Purification of Active Photosystem I-Light Harvesting Complex I from Plant Tissues
07:10

Purification of Active Photosystem I-Light Harvesting Complex I from Plant Tissues

Published on: February 3, 2023

1.6K
Evaluation of Photosynthetic Behaviors by Simultaneous Measurements of Leaf Reflectance and Chlorophyll Fluorescence Analyses
10:20

Evaluation of Photosynthetic Behaviors by Simultaneous Measurements of Leaf Reflectance and Chlorophyll Fluorescence Analyses

Published on: August 9, 2019

13.2K
Separation of Spinach Thylakoid Protein Complexes by Native Green Gel Electrophoresis and Band Characterization using Time-Correlated Single Photon Counting
08:40

Separation of Spinach Thylakoid Protein Complexes by Native Green Gel Electrophoresis and Band Characterization using Time-Correlated Single Photon Counting

Published on: February 14, 2019

8.7K

Area of Science:

  • Plant biology
  • Photosynthesis research
  • Structural biology

Background:

  • Higher plants utilize Photosystem I (PSI) and its Light-Harvesting Complex I (LHCI) antenna to absorb far-red light, prevalent under vegetation canopies.
  • This absorption is facilitated by long-wavelength chlorophylls (Chls) within the Lhca3 and Lhca4 subunits, forming the 'red cluster' (Chls a603 and a609).

Purpose of the Study:

  • To elucidate the molecular mechanisms and structural determinants responsible for far-red light absorption in plant PSI-LHCI complexes.
  • To investigate the role of specific pigment interactions and electronic states in enabling light capture under shaded conditions.

Main Methods:

  • Generation of an Arabidopsis mutant lacking red-shifted absorption using reverse genetics.
  • High-resolution cryogenic electron microscopy (cryo-EM) to determine structures of wild-type and mutant PSI-LHCI complexes.
  • Quantum mechanics calculations and spectroscopic analysis of transgenic lines with targeted mutations.

Main Results:

  • Cryo-EM structures revealed the architecture of PSI-LHCI complexes.
  • Computed excitonic coupling and quantum mechanics calculations indicated that charge transfer states, in addition to excitonic interactions, are essential for simulating far-red absorption spectra.
  • Mutational analysis identified Chl a615 and violaxanthin as potential contributors to far-red light absorption.

Conclusions:

  • Far-red light absorption in plants is achieved through highly specific tuning of chromophore interactions within the PSI-LHCI complex.
  • Understanding these molecular mechanisms is vital for engineering artificial light-harvesting systems with tailored absorption properties for improved photosynthetic efficiency.